diff --git a/src/lib/utils/contest.ts b/src/lib/utils/contest.ts
index 09133e6d1..14cd15fb5 100644
--- a/src/lib/utils/contest.ts
+++ b/src/lib/utils/contest.ts
@@ -95,6 +95,7 @@ export const classifyContest = (contest_id: string) => {
 // HACK: As of June 2025, the following contests are applicable.
 // Note: The classification logic may need to be revised when new contests are added.
 const ABC_LIKE: ContestPrefix = {
+  caddi2018b: 'CADDi 2018 for Beginners',
   aising2020: 'エイシング プログラミング コンテスト 2020',
   hhkb2020: 'HHKB プログラミングコンテスト 2020',
   panasonic2020: 'パナソニックプログラミングコンテスト 2020',
diff --git a/src/test/lib/utils/test_cases/contest_type.ts b/src/test/lib/utils/test_cases/contest_type.ts
index 9547c49d4..dc733e496 100644
--- a/src/test/lib/utils/test_cases/contest_type.ts
+++ b/src/test/lib/utils/test_cases/contest_type.ts
@@ -187,6 +187,10 @@ export const agc = agcContestIds.map((contestId) =>
 );
 
 export const abcLike = [
+  createTestCaseForContestType('CADDi 2018 for Beginners')({
+    contestId: 'caddi2018b',
+    expected: ContestType.ABC_LIKE,
+  }),
   createTestCaseForContestType('AISing 2020')({
     contestId: 'aising2020',
     expected: ContestType.ABC_LIKE,